CN111574330A - A kind of separation method of crude phenol and organic amine mixture - Google Patents

Abstract

The invention discloses a method for separating a mixture of crude phenol and organic amine, which comprises the following steps: adding water and an organic solvent in the process of separating crude phenol containing organic amine by an acidifying water washing method, so as to obtain a phenol phase containing organic solvent and an aqueous phase containing an acidified aqueous solution of organic amine; rectifying the phenolic phase containing an organic solvent to obtain crude phenol; rectifying the aqueous phase containing an aqueous organic amine acidification solution to obtain an organic amine. The invention can separate crude phenol and organic amine quickly and thoroughly, and has the advantages of simple separation process, continuous or intermittent operation, easy enlargement, easy industrialization implementation, low production cost and the like.

Description

A kind of separation method of crude phenol and organic amine mixture

technical field

The invention relates to the technical field of separation of phenol extracted by phenol oil extraction, in particular to a separation method of crude phenol and organic amine mixture.

Background technique

Raw phenol oil comes from phenol oil of high, medium and low temperature coal tar, direct coal liquefaction, indirect liquefaction, and 170-230°C or wider fractions cut from various raw oil, usually called phenol oil, among which The main components are phenols, neutral oils and some nitrogen-containing compounds. Phenolic substances mainly include phenol, o-cresol, m-p-cresol, xylenol, tricresol and the like. Crude phenol, the phenolic extraction product in phenol oil, is a valuable chemical raw material. High-purity phenol products are widely used in medicine, dyes, engineering plastics, and fine chemicals.

The traditional dephenolization method is the acid-base method, which has the advantages of simple process, high separation efficiency and good quality of crude phenol, so it is the most widely used in industry. However, because this process needs to consume a lot of strong acid and alkali, the production cost is high, and a large amount of phenol-containing wastewater is produced, which causes serious pollution to the environment, and cannot meet the requirements of green chemical environmental protection technology, and has been gradually eliminated.

At present, most of the crude phenols in phenol oil are extracted by extraction method, and the extraction effect is also good. However, organic amine extractants are commonly used in the extraction process. These extractants often cross the boiling points of the main components of crude phenol, or form azeotropes with the main components of crude phenol, thus resulting in the inability of organic amine extractants and crude phenol to pass traditional methods such as rectification. separation and regeneration.

Chinese patents CN106986750B and CN109825322A propose to use organic amine aqueous solution and phenol oil for mixed extraction to obtain a mixture of crude phenol and organic amine, and after acidifying and washing with an acidulant, organic amine and crude phenol are separated and organic amine is recovered. But in fact, it is difficult to completely separate and recover the organic amines in the crude phenol by this simple acidifying water washing. Generally, after many times of acidifying water washing, the organic amine content in the crude phenol can only be reduced to the level of 0.5%. This is far from enough, because the existing national standard GB/T 3711-2008 stipulates that when crude phenol is refined, the content of neutral oil should be below 0.8%, and the content of pyridine base should be below 0.5%; the default industry standard requires Higher, for example, it is necessary to ensure that the neutral oil in the crude phenol is below 0.5%. In the crude phenol obtained by the extraction method, the solvent is also a neutral oil. As long as it contains a little other impurities, the quality of the crude phenol will be unqualified. On the other hand, such a simple regeneration requires repeated acidification and water washing many times, which not only makes the crude phenol dissolve in the water to cause losses, but also the water obtained after the washing needs to be regenerated and recovered by rectification, which consumes a large amount of energy, resulting in a long production process, The cost is high, and it has no practical significance in industry.

SUMMARY OF THE INVENTION

In view of the above deficiencies in the prior art, the present invention provides a method for separating crude phenol and organic amine mixture, which can separate crude phenol and organic amine quickly and thoroughly, and solves the problem of existing crude phenol and organic amine. In the amine separation method, many repeated washings are required, the water consumption is too large, a large amount of energy consumption is required for water recovery, the production cost is high, the equipment units are too many, and the organic amine residue in the crude phenol is high, and the separation process is simple. , continuous or intermittent, easy to scale up, easy to implement industrially, low production cost and so on.

The purpose of this invention is to realize through the following technical solutions:

A kind of separation method of crude phenol and organic amine mixture, comprises the following steps:

Step 1, in the process of separating the crude phenol containing the organic amine by the acidified water washing method, add water and an organic solvent, thereby obtaining the phenolic phase containing the organic solvent and the aqueous phase containing the acidified aqueous solution of the organic amine;

Step 2, rectifying the phenolic phase containing the organic solvent, thereby obtaining crude phenol;

Step 3, rectifying the aqueous phase containing the organic amine acidified aqueous solution to obtain the organic amine.

Preferably, in the process of separating the crude phenol containing organic amine by the acidified water washing method, adding water and organic solvent comprises:

Water, an organic solvent, and the crude phenol containing organic amine are mixed together, and an acidifying agent is introduced to carry out acidification treatment, and then the layers are left to stand, and the phenolic phase containing organic solvent and the aqueous phase containing organic amine acidifying aqueous solution are obtained by separation;

or,

Water, organic solvent, and crude phenol containing organic amine are respectively fed into acidifying agent for acidification treatment, then mixed together, and then left to stand for stratification, and the phenolic phase containing organic solvent and the aqueous phase containing organic amine acidified aqueous solution are obtained by separation;

or,

The acidifying agent is introduced into the water for acidification treatment, thereby obtaining acidified water; the acidifying agent is introduced into the crude phenol containing organic amine for acidification treatment, thereby obtaining the crude phenol containing organic amine after acidification; acidified water is used as the heavy phase, with The organic solvent is used as the light phase, and acidified water, organic solvent, and the acidified crude phenol containing organic amine are added to the multistage countercurrent extraction equipment, and separated by multistage countercurrent extraction, thereby obtaining the phenolic phase containing organic solvent and the acidification containing organic amine. The aqueous phase of the aqueous solution.

Preferably, the mass ratio of the organic amine-containing crude phenol to water is 1:0.1-1:2, and the mass ratio of the organic amine-containing crude phenol to the organic solvent is 1:0.1-1:2.

Preferably, the acidulant is carbon dioxide or sulfur dioxide with a volume concentration of 10-100%, and the impurity component is at least one of steam, nitrogen, and rare gas.

Preferably, water, an organic solvent, and crude phenol containing organic amine are mixed together, and an acidifying agent is introduced, mixed and stirred at 20 to 80° C. for 0.1 to 2 hours, and then left to stand for stratification, and the time to stand and stratify is 0.1 ~2h, the phenolic phase containing organic solvent and the aqueous phase containing organic amine acidified aqueous solution were obtained by separation.

Preferably, the acidified water is added to the multistage countercurrent extraction equipment from the first stage, the organic solvent is added to the multistage countercurrent extraction equipment from the last stage, and the acidified crude phenol containing organic amine is added from the last stage to the multistage countercurrent extraction equipment. The second stage or together with the organic solvent is added to the multi-stage countercurrent extraction equipment, and the countercurrent contact completes the extraction and separation.

Preferably, when the organic amine content in the organic solvent-containing phenol phase is greater than 0.1 wt%, the organic solvent-containing phenolic phase is washed with water at least once until the organic solvent-containing phenolic phase has an organic amine content of 0.1 wt% Hereinafter; wherein, the washing of the phenolic phase containing the organic solvent is to mix water with the phenolic phase containing the organic solvent, and feeding an acidulant to carry out acidification treatment, then stand for stratification, and separate the phenolic phase containing the organic solvent and the The water phase containing the organic amine acidified aqueous solution; or, for the water washing of the phenolic phase containing the organic solvent, the water and the phenolic phase containing the organic solvent are respectively fed with an acidifying agent for acidification treatment, then mixed together, and then left to stand for stratification , the phenolic phase containing organic solvent and the aqueous phase containing organic amine acidified aqueous solution were obtained by separation.

Preferably, the mass ratio of the organic solvent-containing phenol phase to water is 1:0.1-1:2.

Preferably, the crude phenol containing organic amine is a heavy phase obtained when phenol oil is extracted, and the content of the organic amine is 10-80 wt%; wherein, the organic amine is C2-C6 alcohol amines, binary amines At least one of alkanolamines.

Preferably, the organic solvent adopts at least one of C4-C8 alcohols, C6-C9 aromatic hydrocarbons, acetates, and ethers.

As can be seen from the technical solutions provided by the present invention, the present invention is to add water and an organic solvent in the process of separating the crude phenol containing the organic amine by the acidified water washing method, so that the crude phenol is dissolved in the organic solvent, and the organic amine is dissolved in the organic solvent. After the amine is acidified, it is mainly soluble in water and basically insoluble in organic solvents, so that the phenolic phase containing organic solvent and the aqueous phase containing organic amine acidified aqueous solution can be quickly and thoroughly separated, and the separation of existing crude phenol and organic amine can be solved. In the method, many repeated water washings are required, the water consumption is too large, a large amount of energy consumption is required when reclaiming water, the production cost is high, the equipment units are too many, the organic amine residue in the crude phenol is high, and the separation process is simple and can be used. Continuous or intermittent, easy to scale up, easy to implement in industrialization, low production cost and so on.

Detailed ways

The technical solutions in the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

The separation method of the crude phenol and organic amine mixture provided by the present invention is described in detail below. Contents that are not described in detail in the embodiments of the present invention belong to the prior art known to those skilled in the art.

(1) a kind of separation method of crude phenol and organic amine mixture

A kind of separation method of crude phenol and organic amine mixture, can comprise the steps:

Step A1, mixing water, organic solvent, and crude phenol containing organic amine, and feeding into acidifying agent for acidification treatment, then standing for stratification, and separating to obtain the phenolic phase containing organic solvent and the water containing organic amine acidifying aqueous solution. Mutually.

Step A2, when the organic amine content in the organic solvent-containing phenol phase is greater than 0.1 wt%, wash the organic solvent-containing phenolic phase with water at least once until the organic solvent-containing phenolic phase has an organic amine content of 0.1 wt% the following.

In step A3, the phenolic phase containing the organic solvent is rectified to obtain crude phenol.

Step A4, rectifying the aqueous phase containing the organic amine acidified aqueous solution to obtain the organic amine.

Specifically, the separation method of the crude phenol and organic amine mixture can include the following embodiments:

(1) The crude phenol containing organic amine is a mixture of crude phenol and organic amine obtained after phenol oil solvent extraction and dephenolization. The organic amine-containing crude phenol is the heavy phase obtained when phenol oil is extracted; for example: the organic amine-containing crude phenol can be phenol oil from high, medium and low temperature coal tar, direct coal liquefaction, indirect The heavy phase obtained when the liquefied product and the 170-230°C or wider fractions cut out of various raw oils are extracted. The organic amine content in the organic amine-containing crude phenol is 10-80 wt %. The organic amine is at least one of C2-C6 alcoholamines and dihydric alcoholamines; the C2-C6 alcoholamines include ethanolamine, diethanolamine, methylethanolamine, dimethylethanolamine, methyl alcohol Diethanolamine, dimethyldiethanolamine, propanolamine, isopropanolamine, dipropanolamine, diisopropanolamine; the diolamines include ethylenediamine, 1,2-propanediamine, 1 , 3-propanediamine, 1,2-butanediamine, 1,3-butanediamine, 1,4-butanediamine.

(2) The organic solvent can be at least one of C4-C8 alcohols, C6-C9 aromatic hydrocarbons, acetates, and ethers. The C4-C8 alcohols include n-butanol, isobutanol, n-amyl alcohol, isoamyl alcohol, n-heptanol, isoheptanol, sec-heptanol, isooctanol, sec-octanol, cyclohexanol, cyclohexanol, Heptanol, etc.; the C6-C9 aromatic hydrocarbons include toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, cumene, etc.; the acetates include n-propyl acetate, isopropyl acetate, n-acetate Butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, etc.; the ethers include isopropyl ether, propyl ether, butyl ether, isobutyl ether, sec-butyl ether, n-amyl ether, isopentyl ether, Ethyl propyl ether, methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), etc.

(3) The acidifying agent is carbon dioxide or sulfur dioxide with a volume concentration of 10-100%, and the impurity component is at least one of steam, nitrogen, and rare gas.

(4) The organic amine-containing crude phenol and water are mixed in a mass ratio of 1:0.1 to 1:2, and the organic amine-containing crude phenol and organic solvent are mixed in a mass ratio of 1:0.1 to 1:2.

(5) In step A1, water, organic solvent, and crude phenol containing organic amine are mixed together, and an acidulant is introduced, mixed and stirred for 0.1 to 2 h at 20 to 80° C. The layer time is 0.1-2h, the upper layer is a phenolic phase containing an organic solvent, and the lower layer is an aqueous phase containing an organic amine acidified aqueous solution, and the organic solvent-containing phenolic phase and the organic amine acidified aqueous solution are separated.

(6) In step A2, the number of times of washing the organic solvent-containing phenol phase with water is 1 to 4 times. ①Washing the phenolic phase containing organic solvent is to mix water with the phenolic phase containing organic solvent, add acidifying agent for acidification, and then stand for stratification to separate the phenolic phase containing organic solvent and the organic amine containing organic amine. The aqueous phase of the acidified aqueous solution. Specifically, for the water washing of the organic solvent-containing phenol phase, water and the organic solvent-containing phenol phase are mixed in a mass ratio of 1:0.1 to 1:2, and an acidulant is introduced, and the mixture is stirred at 20 to 80 °C. 0.1～2h, then stand for stratification, and stand for stratification for 0.1～2h, the upper layer is a phenolic phase containing an organic solvent, the lower layer is an aqueous phase containing an organic amine acidified aqueous solution, and the phenolic phase containing an organic solvent and a phenolic phase containing an organic amine are separated. The aqueous phase of the organic amine acidified aqueous solution. Or, 2. the washing of the phenolic phase containing the organic solvent is that water and the phenolic phase containing the organic solvent are respectively fed into the acidifying agent for acidification treatment, then mixed together, and then left to stand for stratification, and the phenolic phase containing the organic solvent is separated and obtained. phase and an aqueous phase containing an aqueous organic amine acidification solution. Specifically, the mass ratio of the organic solvent-containing phenol phase to water is 1:0.1 to 1:2.

(7) in step A3, adopt rectifying tower to carry out rectification to the phenolic phase containing organic solvent, reclaim and obtain organic solvent and a small amount of water from tower top, all can recycle; Obtain from tower bottom that does not contain water, organic solvent, organic solvent Crude phenol product of amine; the theoretical plate number of the rectification column is 5-40, and the operating pressure can be 10-150kPa (absolute pressure). In practical application, it is better to rectify the phenolic phase containing organic solvent with the content of organic amine below 0.1 wt%, so as to obtain crude phenol.

(8) in step A4, adopt rectifying tower to carry out rectification to the water phase containing organic amine acidification aqueous solution, and extract water and a small amount of organic solvent from tower top, obtain regenerated organic amine from tower still. Acidulant, water, organic solvent and organic amine can all be recycled; the theoretical plate number of the rectifying tower is 5-40, and the operating pressure can be 10-150kPa (absolute pressure).

(9) Step A3 and Step A4 have no sequence, and can be run in parallel.

(2) a kind of separation method of crude phenol and organic amine mixture

A kind of separation method of crude phenol and organic amine mixture, can comprise the steps:

Step B1, water, organic solvent, and crude phenol containing organic amine are respectively fed into acidifying agent to carry out acidification treatment, then mixed together, and then left to stand for stratification, and the phenolic phase containing organic solvent and the aqueous solution containing organic amine are obtained by separation. water box.

Step B2, when the organic amine content in the organic solvent-containing phenol phase is greater than 0.1 wt%, wash the organic solvent-containing phenolic phase with water at least once until the organic solvent-containing phenolic phase has an organic amine content of 0.1 wt% the following.

Step B3, rectifying the phenolic phase containing the organic solvent to obtain crude phenol.

Step B4, rectifying the aqueous phase containing the organic amine acidified aqueous solution to obtain the organic amine.

Specifically, the separation method of the crude phenol and organic amine mixture can include the following embodiments:

(1) The crude phenol containing organic amine is a mixture of crude phenol and organic amine obtained after phenol oil solvent extraction and dephenolization. The organic amine-containing crude phenol is the heavy phase obtained when phenol oil is extracted; for example: the organic amine-containing crude phenol can be phenol oil from high, medium and low temperature coal tar, direct coal liquefaction, indirect The heavy phase obtained when the liquefied product and the 170-230°C or wider fractions cut out of various raw oils are extracted. The organic amine content in the organic amine-containing crude phenol is 10-80 wt %. The organic amine is at least one of C2-C6 alcoholamines and dihydric alcoholamines; the C2-C6 alcoholamines include ethanolamine, diethanolamine, methylethanolamine, dimethylethanolamine, methyl alcohol Diethanolamine, dimethyldiethanolamine, propanolamine, isopropanolamine, dipropanolamine, diisopropanolamine; the diolamines include ethylenediamine, 1,2-propanediamine, 1 , 3-propanediamine, 1,2-butanediamine, 1,3-butanediamine, 1,4-butanediamine.

(2) The organic solvent can be at least one of C4-C8 alcohols, C6-C9 aromatic hydrocarbons, acetates, and ethers. The C4-C8 alcohols include n-butanol, isobutanol, n-amyl alcohol, isoamyl alcohol, n-heptanol, isoheptanol, sec-heptanol, isooctanol, sec-octanol, cyclohexanol, cyclohexanol, Heptanol, etc.; the C6-C9 aromatic hydrocarbons include toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, cumene, etc.; the acetates include n-propyl acetate, isopropyl acetate, n-acetate Butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, etc.; the ethers include isopropyl ether, propyl ether, butyl ether, isobutyl ether, sec-butyl ether, n-amyl ether, isopentyl ether, Ethyl propyl ether, methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), etc.

(3) The acidifying agent is carbon dioxide or sulfur dioxide with a volume concentration of 10-100%, and the impurity component is at least one of steam, nitrogen, and rare gas.

(4) The mass ratio of the organic amine-containing crude phenol to water is 1:0.1 to 1:2, and the mass ratio of the organic amine-containing crude phenol to the organic solvent is 1:0.1 to 1:2.

(5) In step B1, water, organic solvent, and crude phenol containing organic amine are respectively fed with an acidulant, and are mixed and stirred at 20-80° C. for 0.1-2 h, then mixed together, and then left to stand for stratification. The stratification time is 0.1-2h, the upper layer is a phenolic phase containing an organic solvent, and the lower layer is an aqueous phase containing an organic amine acidified aqueous solution.

(6) In step B2, the number of times of washing the organic solvent-containing phenol phase with water is 1 to 4 times. ①Washing the phenolic phase containing organic solvent is to mix water with the phenolic phase containing organic solvent, add acidifying agent for acidification, and then stand for stratification to separate the phenolic phase containing organic solvent and the organic amine containing organic amine. The aqueous phase of the acidified aqueous solution. Specifically, for the water washing of the organic solvent-containing phenol phase, water and the organic solvent-containing phenol phase are mixed in a mass ratio of 1:0.1 to 1:2, and an acidulant is introduced, and the mixture is stirred at 20 to 80 °C. 0.1～2h, then stand for stratification, and stand for stratification for 0.1～2h, the upper layer is a phenolic phase containing an organic solvent, the lower layer is an aqueous phase containing an organic amine acidified aqueous solution, and the phenolic phase containing an organic solvent and a phenolic phase containing an organic amine are separated. The aqueous phase of the organic amine acidified aqueous solution. Or, 2. the washing of the phenolic phase containing the organic solvent is that water and the phenolic phase containing the organic solvent are respectively fed into the acidifying agent for acidification treatment, then mixed together, and then left to stand for stratification, and the phenolic phase containing the organic solvent is separated and obtained. phase and an aqueous phase containing an aqueous organic amine acidification solution. Specifically, the mass ratio of the organic solvent-containing phenol phase to water is 1:0.1 to 1:2.

(7) in step B3, adopt rectifying tower to carry out rectification to the phenolic phase containing organic solvent, reclaim from tower top and obtain organic solvent and a small amount of water, all can recycle; Obtain from tower bottom that does not contain water, organic solvent, organic Crude phenol product of amine; the theoretical plate number of the rectification column is 5-40, and the operating pressure can be 10-150kPa (absolute pressure). In practical application, it is better to rectify the phenolic phase containing organic solvent with the content of organic amine below 0.1 wt%, so as to obtain crude phenol.

(8) in step B4, adopt rectifying tower to carry out rectification to the aqueous phase containing organic amine acidification aqueous solution, from the top of tower, produce water and a small amount of organic solvent, obtain regenerated organic amine from tower still. Acidulant, water, organic solvent and organic amine can all be recycled; the theoretical plate number of the rectifying tower is 5-40, and the operating pressure can be 10-150kPa (absolute pressure).

(9) Step B3 and Step B4 have no sequence, and can be run in parallel.

(3) a kind of separation method of crude phenol and organic amine mixture

A kind of separation method of crude phenol and organic amine mixture, can comprise the steps:

Step C1, feed an acidifying agent into the water for acidification treatment, thereby obtaining acidified water; feed an acidifying agent into the crude phenol containing organic amines for acidification treatment, thereby obtaining the crude phenol containing organic amines after acidification; take acidified water as the weight. Phase, take the organic solvent as the light phase, add acidified water, organic solvent, acidified crude phenol containing organic amine into the multistage countercurrent extraction equipment, multistage countercurrent extraction and separation, thereby obtaining the phenolic phase containing organic solvent and the organic The aqueous phase of the amine acidified aqueous solution.

In step C2, the phenolic phase containing the organic solvent is rectified to obtain crude phenol.

Step C3, rectifying the aqueous phase containing the organic amine acidified aqueous solution to obtain the organic amine.

Specifically, the separation method of the crude phenol and organic amine mixture can include the following embodiments:

(1) The crude phenol containing organic amine is a mixture of crude phenol and organic amine obtained after phenol oil solvent extraction and dephenolization. The organic amine-containing crude phenol is the heavy phase obtained when phenol oil is extracted; for example: the organic amine-containing crude phenol can be phenol oil from high, medium and low temperature coal tar, direct coal liquefaction, indirect The heavy phase obtained when the liquefied product and the 170-230°C or wider fractions cut out of various raw oils are extracted. The organic amine content in the organic amine-containing crude phenol is 10-80 wt %. The organic amine is at least one of C2-C6 alcoholamines and dihydric alcoholamines; the C2-C6 alcoholamines include ethanolamine, diethanolamine, methylethanolamine, dimethylethanolamine, methyl alcohol Diethanolamine, dimethyldiethanolamine, propanolamine, isopropanolamine, dipropanolamine, diisopropanolamine; the diolamines include ethylenediamine, 1,2-propanediamine, 1 , 3-propanediamine, 1,2-butanediamine, 1,3-butanediamine, 1,4-butanediamine.

(2) The organic solvent can be at least one of C4-C8 alcohols, C6-C9 aromatic hydrocarbons, acetates, and ethers. The C4-C8 alcohols include n-butanol, isobutanol, n-amyl alcohol, isoamyl alcohol, n-heptanol, isoheptanol, sec-heptanol, isooctanol, sec-octanol, cyclohexanol, cyclohexanol, Heptanol, etc.; the C6-C9 aromatic hydrocarbons include toluene, xylene, ethylbenzene, trimethylbenzene, methylethylbenzene, cumene, etc.; the acetates include n-propyl acetate, isopropyl acetate, n-acetate Butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, etc.; the ethers include isopropyl ether, propyl ether, butyl ether, isobutyl ether, sec-butyl ether, n-amyl ether, isopentyl ether, Ethyl propyl ether, methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), etc.

(3) The acidifying agent is carbon dioxide or sulfur dioxide with a volume concentration of 10-100%, and the impurity component is at least one of steam, nitrogen, and rare gas.

(4) The mass ratio of the organic amine-containing crude phenol to water is 1:0.1 to 1:2, and the mass ratio of the organic amine-containing crude phenol to the organic solvent is 1:0.1 to 1:2.

(5) in step C1, pass acidifying agent into water and carry out acidification treatment, thereby obtain acidified water; In the crude phenol containing organic amine, feed acidifying agent and carry out acidification treatment, thus obtain the crude phenol containing organic amine after acidification; Using acidified water as the heavy phase and organic solvent as the light phase, the acidified water, the organic solvent, and the acidified crude phenol containing organic amines are added to the multi-stage countercurrent extraction equipment, and the acidified crude phenol containing organic amines flows from the multistage countercurrent. It is added at a certain stage in the middle of the extraction equipment, and separated by multistage countercurrent extraction, and the number of extraction stages is 3 to 10, thereby obtaining a phenolic phase containing an organic solvent and an aqueous phase containing an acidified aqueous solution of an organic amine. If the acidified water is added to the multi-stage countercurrent extraction equipment from the first stage, the organic solvent is added to the multistage countercurrent extraction device from the penultimate stage, and the acidified crude phenol containing organic amines is added from the penultimate The 2-stage or together with the organic solvent is added to the multi-stage countercurrent extraction equipment, and the countercurrent contacting completes the extraction. The extraction equipment can be a centrifugal extractor, an extraction tower, a mixing tank, and a mixing and clarifying tank. If the extraction equipment adopts an extraction tower, the organic solvent should be added from the bottom of the tower, acidified water should be added from the top of the tower, and the crude phenol containing organic amine after acidification should be added from the bottom of the tower together with the organic solvent, or added at one stage above the organic solvent inlet. .

(6) in step C2, adopt rectifying tower to carry out rectification to the phenolic phase containing organic solvent, reclaim from tower top and obtain organic solvent and a small amount of water, all can recycle; Obtain from tower bottom that does not contain water, organic solvent, organic Crude phenol product of amine; the theoretical plate number of the rectification column is 5-40, and the operating pressure can be 10-150kPa (absolute pressure). In practical application, it is better to rectify the phenolic phase containing organic solvent with the content of organic amine below 0.1 wt%, so as to obtain crude phenol.

(7) in step C3, adopt rectifying tower to carry out rectification to the aqueous phase containing organic amine acidification aqueous solution, from tower top production water and a small amount of organic solvent, obtain regenerated organic amine from tower still. Acidulant, water, organic solvent and organic amine can all be recycled; the theoretical plate number of the rectifying tower is 5-40, and the operating pressure can be 10-150kPa (absolute pressure).

(8) Step C2 and Step C3 have no sequence, and can be run in parallel.

(4) Advantages of the present invention

Compared with the prior art, the present invention has at least the following advantages:

(1) the present invention is in the separation process of crude phenol and organic amine, suitably adds organic solvent, this makes crude phenol dissolve in organic solvent, and organic amine itself is water-soluble organic matter, is mainly water-soluble after being acidified, Basically insoluble in organic solvents, so that organic amines and crude phenols can be well separated.

(2) Due to the low viscosity and good fluidity of the organic solvent, the organic solvent phase in which the crude phenol is dissolved and the water phase in which the organic amine is dissolved can quickly and thoroughly achieve layering, which avoids the entrainment of organic amines in the crude phenol, and also avoids the The crude phenol is entrained in the organic amine, thereby significantly improving the separation effect, reducing the standing time required for the separation process, and making the separation process easy to enlarge, operate and continuous.

(3) Due to the above-mentioned reasons, the required water washing times, the number of equipment units and equipment investment, the total water consumption, and the energy consumption required for the reclaimed water in the separation of the crude phenol and the organic amine are greatly reduced, thereby significantly reducing the production cost.

(4) the separation method of the crude phenol provided by the present invention and the organic amine mixture, the organic amine content in the crude phenol can be easily controlled below 0.1wt%, significantly reducing the neutral oil and the pyridine base content in the crude phenol, It is significantly better than the technical index of reducing the organic amine in the crude phenol to 0.5% in the prior art, also reduces the loss of the extractant, and further reduces the production cost.

(5) the separation method of crude phenol and organic amine mixture provided by the present invention adopts rectification method to separate organic amine and water, significantly improves the separation effect of organic amine and water and acidulant, and makes organic amine fully regenerated and recovered. When used, it can exert the best extraction effect and significantly reduce the energy consumption of the production process.

To sum up, it can be seen that the embodiment of the present invention can quickly and thoroughly separate crude phenol and organic amine, and solves the problem that in the existing crude phenol and organic amine separation method, repeated washing with water, excessive water consumption, and recycling of water are required. It needs a lot of energy consumption, high production cost, too many equipment units, high residual organic amine in crude phenol, and has the advantages of simple separation process, continuous or intermittent, easy to scale up, easy to industrialize implementation, and low production cost.

In order to more clearly demonstrate the technical solutions provided by the present invention and the resulting technical effects, the following specific examples are used to describe the separation method of the crude phenol and organic amine mixture provided by the embodiments of the present invention in detail.

Example 1

A method for separating crude phenol and organic amine mixture, which is used for treating crude phenol (containing 40% of diethanolamine) containing organic amine obtained by extraction of phenol oil fraction (distillation range 170-230° C.) from medium temperature tar, It includes the following steps:

Step a1, the described crude phenol containing organic amines of 1000kg, 1200kg water, 800kg organic solvent xylene (1/3 of each o-xylene, m-xylene, p-xylene) are added simultaneously in the stirring reaction kettle to mix and stir, with At the same time, CO ₂ (the impurity components are water vapor and nitrogen) with a content of 60% was passed into the bottom of the reaction kettle, so that the gas and liquid were fully contacted and reacted, mixed and stirred at 65 ° C for 1.2 h, and then stood for stratification and separated. A phenolic phase containing an organic solvent (ie, a mixed solution of crude phenol from which diethanolamine has been removed and xylene) and an aqueous phase containing an organic amine acidified aqueous solution (ie, an aqueous diethanolamine solution) are obtained.

Step a2, the phenolic phase containing organic solvent is washed once; the phenolic phase containing organic solvent obtained in step a1 and 1200kg water are added simultaneously in the stirring reaction kettle to mix and stir, meanwhile, feed content 60% at the bottom of this reaction kettle. % CO ₂ (the impurity components are water vapor and nitrogen), make the gas-liquid fully contact and react, mix and stir at 65 ° C for 1.2 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, remove the A mixed solution of crude phenol of diethanolamine and xylene) and an aqueous phase containing an acidified aqueous solution of organic amine (ie, an aqueous solution of diethanolamine).

Step a3, adding the phenolic phase containing the organic solvent obtained in step a2 into a rectifying tower with a pressure of 50 kPa and 25 plates for rectification, and obtaining organic solvent xylene and a small amount of water at the top of the tower, which can be recycled; The crude phenol product without organic solvent, diethanolamine and water, wherein the content of diethanolamine is 0.02%.

Step a4, the aqueous phase containing the organic amine acidified aqueous solution obtained in step a1 and the aqueous phase containing the organic amine acidified aqueous solution obtained in step a2 are pumped into a rectifying tower with a pressure of 50 kPa and 25 plates to carry out rectification, and the top of the tower is rectified. _CO2 gas, water and a small amount of xylene are produced, which can be recycled; the regenerated diethanolamine is obtained from the tower still, and the phenol content is 1.3%, which can be recycled.

Specifically, the main process parameters of Example 1 of the present invention are shown in Table 1 below:

Table 1

Example 2

A method for separating crude phenol and organic amine mixture, which is used for crude phenol (containing 60% of 1,2-propanediamine) containing organic amine obtained by extraction of phenol oil fraction (130-280° C.) from low-temperature tar processing, including the following steps:

Step b1, the described crude phenol containing organic amines of 1000kg, 2000kg water, 500kg organic solvent (sec-octanol: isooctanol=2:3) are added simultaneously in the stirring reaction kettle to mix and stir, simultaneously in this reaction kettle The bottom is fed with 80% CO ₂ (the impurity components are steam and nitrogen) to make the gas and liquid fully contact and react, mix and stir at 70 ° C for 1.5 h, and then stand for stratification to separate the phenol containing organic solvent. Phase (ie, the mixed solution of crude phenol and organic solvent from which 1,2-propanediamine has been removed) and an aqueous phase (ie, aqueous 1,2-propanediamine solution) containing an acidified aqueous solution of organic amine.

Step b2, the phenolic phase containing the organic solvent is washed once; the phenolic phase containing the organic solvent obtained in step b1 and 2000kg of water are simultaneously added to the stirring reaction kettle to mix and stir, and simultaneously at the bottom of the reaction kettle, a content of 80% is added. % CO ₂ (the impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 70 ° C for 1.5 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, remove the A mixed solution of crude phenol of 1,2-propanediamine and an organic solvent) and an aqueous phase containing an acidified aqueous solution of organic amine (ie, an aqueous solution of 1,2-propanediamine).

Step b3, adding the phenolic phase containing the organic solvent obtained in step b2 into a rectifying tower with a pressure of 110 kPa and 40 plates for rectification, obtaining an organic solvent and a small amount of water at the top of the tower, which can be recycled; The crude phenol product of organic solvent, 1,2-propanediamine and water, wherein the content of 1,2-propanediamine is 0.08%.

Step b4, pump the aqueous phase containing the organic amine acidified aqueous solution obtained in step b1 and the aqueous phase containing the organic amine acidified aqueous solution obtained in step b2 into a rectifying tower with a pressure of 110 kPa and 40 plates for rectification. CO ₂ gas, water and a small amount of organic solvent are produced, which can be recycled; the tower still obtains regenerated 1,2-propanediamine, in which the phenol content is 2.5%, which can be recycled.

Specifically, the main process parameters of Example 2 of the present invention are shown in Table 2 below:

Table 2

Example 3

A method for separating crude phenol and organic amine mixture, for processing crude phenol containing organic amine (containing 70% of ethanolamine and ethylenediamine, referred to as mixed amine in the present embodiment) obtained by extraction from medium-temperature tar, comprising: Follow the steps below:

Step c1, the described crude phenol containing organic amine of 1000kg, 1200kg water, 300kg organic solvent (isopropyl ether: propyl ether=1:1) are added in the stirring reactor simultaneously and mix and stir, simultaneously at the bottom of the reactor Introduce CO ₂ with a content of 90% (the impurity components are water vapor and nitrogen), make the gas-liquid fully contact and react, mix and stir at 55 ° C for 1 h, then stand for stratification, and separate to obtain a phenolic phase containing an organic solvent ( That is, the mixed solution of crude phenol and organic solvent from which mixed amines are removed) and the aqueous phase (ie mixed amine solution) containing the acidified aqueous solution of organic amines.

Step c2, the phenolic phase containing organic solvent is washed for the first time; the phenolic phase containing organic solvent obtained in step c1 and 1200kg water are simultaneously added to the stirring reaction kettle and mixed and stirred, and at the same time pass into the bottom of the reaction kettle. CO ₂ with a content of 90% (the impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 55 ° C for 1 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, to remove the organic solvent). Except the mixed solution of crude phenol and organic solvent of mixed amine) and the aqueous phase (ie mixed amine solution) containing the acidified aqueous solution of organic amine.

Step c3, the phenolic phase containing organic solvent is washed for the second time; the phenolic phase containing organic solvent obtained in step c2 and 1200kg water are simultaneously added to the stirring reaction kettle and mixed and stirred at the same time at the bottom of the reaction kettle. CO ₂ with a content of 90% (the impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 55 ° C for 1 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, to remove the organic solvent). In addition to the mixed solution of mixed amine crude phenol and organic solvent) and the aqueous phase containing organic amine acidified aqueous solution (ie mixed amine solution).

Step c4, adding the phenolic phase containing the organic solvent obtained in step c3 into a rectifying tower with a pressure of 150 kPa and 25 plates for rectification, obtaining organic solvent and a small amount of water at the top of the tower, which can be recycled; The crude phenol product of organic solvent, mixed amine and water, wherein the mixed amine content is 0.06%.

Step c5, pump the aqueous phase containing the organic amine acidified aqueous solution obtained in step c1, the aqueous phase containing the organic amine acidified aqueous solution obtained in step c2 and the aqueous phase containing the organic amine acidified aqueous solution obtained in step c3 together. The pressure is 150kPa, 25 The rectification is carried out in a block-plate rectification tower, and _CO2 gas, water, and a small amount of organic solvent are extracted from the top of the tower, which can be recycled; the tower still obtains regenerated ethanolamine and ethylenediamine, of which the phenol content is 3.5%, which can be recycled. .

Specifically, the main process parameters of Example 3 of the present invention are shown in Table 3 below:

table 3

Example 4

A method for separating crude phenol and organic amine mixture, for treating crude phenol (containing 60% of dimethylethanolamine) containing organic amine obtained from medium temperature tar extraction, comprising the following steps:

Step d1, the described crude phenol containing organic amine of 1000kg, 2000kg water, 300kg organic solvent (ethyl tertiary butyl ether) are added in stirring reactor simultaneously and mix and stir, meanwhile, pass into content 80% at the bottom of this reactor. % CO ₂ (the impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 50 ° C for 1.5 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, remove the A mixed solution of crude phenol of dimethylethanolamine and ethyl tert-butyl ether) and an aqueous phase containing an acidified aqueous solution of an organic amine (ie, an aqueous solution of dimethylethanolamine).

Step d2, the phenolic phase containing organic solvent is washed once; the phenolic phase containing organic solvent obtained in step d1 and 2000kg of water are simultaneously added to the stirring reaction kettle for mixing and stirring, and meanwhile, a content of 80% is passed at the bottom of the reaction kettle. % CO ₂ (the impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 50 ° C for 1.5 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, remove the A mixed solution of crude phenol of dimethylethanolamine and ethyl tert-butyl ether) and an aqueous phase containing an acidified aqueous solution of an organic amine (ie, an aqueous solution of dimethylethanolamine).

Step d3, adding the phenolic phase containing the organic solvent obtained in step d2 into a rectifying tower with a pressure of 110 kPa and 5 plates for rectification, and obtaining organic solvent ethyl tertiary butyl ether and a small amount of water at the top of the tower, which can be recycled. ; The crude phenol product that does not contain organic solvent, dimethylethanolamine and water is obtained at the bottom of the tower, wherein the content of dimethylethanolamine is 0.02%.

Step d4, pump the aqueous phase containing the organic amine acidified aqueous solution obtained in step d1 and the aqueous phase containing the organic amine acidified aqueous solution obtained in step d2 into a rectifying tower with a pressure of 110 kPa and 5 plates for rectification, and the top of the tower is rectified. _CO2 gas, water and a small amount of organic solvent ethyl tertiary butyl ether are produced, which can be recycled; the tower still obtains regenerated dimethylethanolamine, wherein the phenol content is 1.5%, which can be recycled.

Specifically, the main process parameters of Example 4 of the present invention are shown in Table 4 below:

Table 4

Example 5

A kind of separation method of crude phenol and organic amine mixture, is used for the crude phenol (containing 5% propanolamine and 5% isopropanolamine, organic amine total 10%) containing organic amine obtained from medium temperature tar extraction. processing, including the following steps:

Step e1, the described crude phenol containing organic amine of 1000kg, 500kg water, 2000kg organic solvent (n-heptanol) are added in the stirring reactor simultaneously and mix and stir, meanwhile, pass into the CO of content 10% at the bottom of this reactor ₂ (The impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 35 ° C for 0.1 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, remove the propanolamine). A mixed solution of crude phenol and n-heptanol with isopropanolamine) and an aqueous phase containing an aqueous solution of organic amine acidification (ie, aqueous solutions of propanolamine and isopropanolamine).

Step e2, adding the phenolic phase containing the organic solvent obtained in step e1 into a rectifying tower with a pressure of 10 kPa and 5 plates for rectification, and obtaining organic solvent n-heptanol and a small amount of water at the top of the tower, which can be recycled; Crude phenol product without organic solvent, organic amine and water, wherein the organic amine content is 0.07%.

Step e3, the aqueous phase containing the organic amine acidified aqueous solution obtained in step e1 is pumped into a rectifying tower with a pressure of 10 kPa and 5 plates for rectification, and _CO gas, water, and a small amount of organic solvent n-heptanol are extracted from the top of the tower. , can be recycled; the tower still obtains regenerated propanolamine and isopropanolamine, wherein the phenol content is 1.5%, which can be recycled.

Specifically, the main process parameters of Example 5 of the present invention are shown in Table 5 below:

table 5

Example 6

A method for separating crude phenol and organic amine mixture, which is used for treating crude phenol (containing 20% ethanolamine) containing organic amine obtained from medium temperature tar extraction, comprising the following steps:

Step f1, use CO ₂ with a content of 30% to acidify with water and the crude phenol containing organic amines in a gas-liquid contact device respectively, so as to obtain acidified water and crude phenol containing organic amines after acidification; Extraction is carried out in the tower, acidified water is added at a rate of 100kg/h from the first stage of the extraction tower as a heavy phase (the sequence number is from top to bottom), and an organic solvent (n-butanol) is added as a light phase from the extraction tower. The 10th stage was added at a rate of 1500kg/h, and the crude phenol containing organic amines after acidification was added at a rate of 1000kg/h from the 9th stage of the extraction column. The operating temperature of the extraction column was 50°C under normal pressure. After the extraction is completed, the mixed solution of the crude phenol and n-butanol that has removed the organic amine is obtained at the top of the extraction tower (that is, the phenolic phase containing the organic solvent), and the bottom of the extraction tower is obtained. water box).

Step f2, adding the phenolic phase containing the organic solvent obtained in step f1 into a rectifying tower with a pressure of 10 kPa and 5 plates for rectification, and obtaining organic solvent n-butanol and a small amount of water at the top of the tower, which can be recycled; Crude phenol product without organic solvent, ethanolamine and water, wherein the content of ethanolamine is 0.05%.

Step f3, the aqueous phase containing the organic amine acidified aqueous solution obtained in step f1 is pumped into a rectifying tower with a pressure of 10kPa and 5 plates for rectification, and _CO gas, water, and a small amount of organic solvent n-butanol are extracted from the top of the tower. , which can be recycled; the tower still obtains regenerated ethanolamine, wherein the phenol content is 2.5%, which can be recycled.

Specifically, the main process parameters of Example 6 of the present invention are shown in Table 6 below:

Table 6

Example 7

A method for separating crude phenol and organic amine mixture, which is used for treating crude phenol (containing 30% methylethanolamine) containing organic amine obtained by extraction of medium-temperature tar, comprising the following steps:

Step g1, use SO ₂ (the impurity component is nitrogen gas) with a content of 60% to be acidified with water and the crude phenol containing organic amines in a gas-liquid contact device respectively, so as to obtain acidified water and acidified crude acid containing organic amines. Phenol; Extraction is carried out in a 3-stage countercurrent extraction tower, and acidified water is added at a rate of 900 kg/h from the first stage of the extraction tower as a heavy phase (stage numbering is in the order from top to bottom), and an organic solvent (cumene ) with the crude phenol containing organic amine after acidification and add from the 3rd stage of extraction tower, organic solvent (cumene) is added at the rate of 1000kg/h, and the crude phenol containing organic amine after acidification is added at the rate of 1000kg/h . The operating temperature of the extraction column was 20°C under normal pressure. After the extraction is completed, obtain the mixed solution of the crude phenol that has removed the organic amine and the cumene at the top of the extraction tower (that is, the phenolic phase containing the organic solvent), and the bottom of the extraction tower obtains the organic amine aqueous solution (that is, the aqueous solution containing the organic amine acidification solution). water box).

Step g2, adding the phenolic phase containing the organic solvent obtained in step g1 into a rectifying tower with a pressure of 50 kPa and 25 plates to carry out rectification, and obtaining organic solvent cumene, methyl ethanolamine and a small amount of water at the top of the tower, which can be recycled. use; the crude phenol product without organic solvent, methylethanolamine and water is obtained at the bottom of the tower, wherein the content of methylethanolamine is 0.08%.

Step g3, pumping the aqueous phase containing the organic amine acidified aqueous solution obtained in step g1 into a rectifying tower with a pressure of 50kPa and 25 plates to carry out rectification, and extracting _CO gas, water, a small amount of organic solvent cumene from the top of the tower , can be recycled; the tower still obtains regenerated methylethanolamine, wherein the phenol content is 5%, and can be recycled.

Specifically, the main process parameters of Example 7 of the present invention are shown in Table 7 below:

Table 7

Example 8

A method for separating crude phenol and organic amine mixture, which is used for processing crude phenol (containing 50% of propanolamine) containing organic amine obtained from medium temperature tar extraction, comprising the following steps:

Step h1, the described crude phenol containing organic amine of 1000kg, 1000kg water, 1200kg organic solvent (isopropyl acetate) are added in the stirring reactor simultaneously and mix and stir, meanwhile, pass into the content of 70% at the bottom of the reactor. CO ₂ (the impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 75 ° C for 1.5 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, remove the propanol A mixed solution of crude phenol of amine and isopropyl acetate) and an aqueous phase containing an aqueous solution of acidified organic amine (ie, an aqueous solution of propanolamine).

Step h2, the phenolic phase containing the organic solvent is washed once; the phenolic phase containing the organic solvent obtained in step h1 and 1000kg of water are simultaneously added to the stirring reaction kettle to mix and stir, while the reaction kettle bottom is fed with a content of 70%. % CO ₂ (the impurity components are water vapor and nitrogen), make the gas-liquid fully contact and react, mix and stir at 75 ° C for 1.5 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, remove the A mixed solution of crude phenol of propanolamine and isopropyl acetate) and an aqueous phase containing an acidified aqueous solution of organic amine (ie, an aqueous solution of propanolamine).

Step h3, adding the phenolic phase containing the organic solvent obtained in step h2 into a rectifying tower with a pressure of 50 kPa and 40 plates for rectification, and obtaining organic solvent isopropyl acetate and a small amount of water at the top of the tower, which can be recycled; The crude phenol product without organic solvent, propanolamine and water is obtained at the bottom, wherein the content of propanolamine is 0.09%.

Step h4, the aqueous phase containing the organic amine acidified aqueous solution obtained in step h1 and the aqueous phase containing the organic amine acidified aqueous solution obtained in step h2 are pumped into a rectifying tower with a pressure of 50 kPa and 40 plates for rectification, and the top of the tower is _CO2 gas, water and a small amount of organic solvent isopropyl acetate are produced, which can be recycled; the tower still obtains regenerated propanolamine, wherein the phenol content is 2.5%, which can be recycled.

Specifically, the main process parameters of Embodiment 8 of the present invention are shown in Table 8 below:

Table 8

Example 9

A method for separating crude phenol and organic amine mixture, which is used for treating crude phenol (containing 30% of 1,3-propanediamine) containing organic amine obtained from medium temperature tar extraction, comprising the following steps:

Step I1, the described crude phenol containing organic amine of 1000kg, 300kg water, 1600kg organic solvent (butyl acetate: isobutyl acetate=1:1) are added in the stirring reactor simultaneously and mix and stir, simultaneously in this reaction The bottom of the kettle was fed with 50% CO ₂ (the impurity components were water vapor and nitrogen) to make the gas and liquid fully contact and react, mixed and stirred at 65°C for 1 hour, and then left to stand for stratification to separate the phenol containing organic solvent. phase (ie, the mixed solution of crude phenol and organic solvent from which 1,3-propanediamine has been removed) and an aqueous phase (ie, aqueous 1,3-propanediamine solution) containing an acidified aqueous solution of organic amine.

Step I2, the phenolic phase containing organic solvent is washed for the first time; The phenolic phase containing organic solvent obtained in step I1 and 300kg water are added in the stirring reaction kettle simultaneously and mix and stir, meanwhile, pass into the bottom of this reaction kettle. CO ₂ with a content of 50% (the impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 65 ° C for 1 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, to remove the organic solvent). Except for the mixed solution of crude phenol and organic solvent of 1,3-propanediamine) and the aqueous phase containing the acidified aqueous solution of organic amine (ie 1,3-propanediamine aqueous solution).

Step 13, the phenolic phase containing organic solvent is washed for the second time; the phenolic phase containing organic solvent obtained in step 12 and 300kg water are added in the stirring reaction kettle simultaneously and mix and stir, meanwhile, pass into the bottom of this reaction kettle. CO ₂ with a content of 50% (the impurity components are water vapor and nitrogen), make the gas and liquid fully contact and react, mix and stir at 65 ° C for 1 h, then stand for stratification, and separate the phenolic phase containing the organic solvent (that is, to remove the organic solvent). Except for the mixed solution of crude phenol and organic solvent of 1,3-propanediamine) and the aqueous phase containing the acidified aqueous solution of organic amine (ie 1,3-propanediamine aqueous solution).

Step 14, adding the phenolic phase containing the organic solvent obtained in step 13 into a rectifying tower with a pressure of 150 kPa and 25 plates to carry out rectification, and the top of the tower obtains an organic solvent and a small amount of water, which can be recycled; The crude phenol product of organic solvent, 1,3-propanediamine and water, wherein the content of 1,3-propanediamine is 0.1%.

Step I5, the aqueous phase containing the organic amine acidifying aqueous solution obtained in step I1, the aqueous phase containing the organic amine acidifying aqueous solution obtained in step I2 and the aqueous phase containing the organic amine acidifying aqueous solution obtained in step I3 are pumped together at a pressure of 150kPa, 25 The rectification is carried out in the rectification tower of the block plate, and _CO2 gas, water and a small amount of organic solvent are extracted from the top of the tower, which can be recycled; the regenerated 1,3-propanediamine is obtained from the tower still, and the phenol content is 5%, which can be recycled. recycle.

Specifically, the main process parameters of Example 9 of the present invention are shown in Table 9 below:

Table 9

Comparative Example 1

Except that the organic solvent xylene is not added, the other operations are exactly the same as in Example 1. As a result, the content of organic amine in the crude phenol product is 24.9%, and the content of phenol in the organic amine obtained by regeneration is 74.2%. It can be seen that the purpose of separating organic amines in crude phenol is not achieved at all. If the organic amine in the crude phenol product is to be removed to less than 0.1%, more than 6 times of water washing operations are required.

Specifically, the main process parameters of Comparative Example 1 are shown in Table 10 below:

Table 10

Comparative Example 2

Except that the organic solvent cumene was not added, the remaining operations were exactly the same as in Implementation 7. As a result, the content of organic amine in the crude phenol product was 18.8%, and the content of phenol in the organic amine obtained by regeneration was 67%.

Specifically, the main process parameters of Comparative Example 2 are shown in Table 11 below:

Table 11

Data comparison

The raw materials, solvents, operating conditions and impurities in the products in the above-mentioned Examples 1 to 9 of the present invention and Comparative Examples 1 to 2 were summarized to obtain the following table 12:

Table 12

It can be seen from Table 12 that the products in Examples 1 to 9 of the present invention all meet the expected standards.

To sum up, it can be seen that the embodiment of the present invention can quickly and thoroughly separate crude phenol and organic amine, and solves the problem that in the existing crude phenol and organic amine separation method, repeated washing with water, excessive water consumption, and recycling of water are required. It needs a lot of energy consumption, high production cost, too many equipment units, high residual organic amine in crude phenol, and has the advantages of simple separation process, continuous or intermittent, easy to scale up, easy to industrialize implementation, and low production cost.

The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited to this. Substitutions should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. A method for separating a mixture of crude phenol and organic amine, comprising the steps of:

step 1, adding water and an organic solvent in the process of separating crude phenol containing organic amine by adopting an acidification water washing method, thereby obtaining a phenol phase containing the organic solvent and a water phase containing an organic amine acidification water solution;

step 2, rectifying the phenol phase containing the organic solvent to obtain crude phenol;

and 3, rectifying the water phase containing the organic amine acidified water solution to obtain the organic amine.

2. The method of claim 1, wherein the adding water and organic solvent during the separating of the crude phenol containing organic amine by the acidified water wash comprises:

mixing water, an organic solvent and crude phenol containing organic amine together, introducing an acidifying agent for acidification treatment, standing for layering, and separating to obtain a phenol phase containing the organic solvent and a water phase containing an organic amine acidified water solution;

or,

respectively introducing water, an organic solvent and crude phenol containing organic amine into an acidifying agent for acidification treatment, then mixing the water, the organic solvent and the crude phenol containing organic amine together, standing for layering, and separating to obtain a phenol phase containing the organic solvent and a water phase containing an organic amine acidified aqueous solution;

or,

acidifying water by introducing an acidifying agent into the water to obtain acidified water; introducing an acidifying agent into the crude phenol containing the organic amine for acidification treatment, thereby obtaining the acidified crude phenol containing the organic amine; and adding the acidified water, the organic solvent and the acidified crude phenol containing the organic amine into multistage countercurrent extraction equipment, and performing multistage countercurrent extraction and separation to obtain a phenol phase containing the organic solvent and a water phase containing the acidified aqueous solution of the organic amine.

3. The method for separating the mixture of the crude phenol and the organic amine according to claim 2, wherein the mass ratio of the crude phenol containing the organic amine to the water is 1:0.1 to 1:2, and the mass ratio of the crude phenol containing the organic amine to the organic solvent is 1:0.1 to 1: 2.

4. The method for separating the mixture of crude phenol and organic amine according to claim 2, wherein the acidifying agent is carbon dioxide or sulfur dioxide with a volume concentration of 10-100%, and the impurity component is at least one of water vapor, nitrogen gas and rare gas.

5. The method for separating the mixture of the crude phenol and the organic amine according to claim 2, wherein the water, the organic solvent and the crude phenol containing the organic amine are mixed together, an acidulant is introduced, the mixture is mixed and stirred for 0.1 to 2 hours at the temperature of 20 to 80 ℃, then the mixture is kept still for layering, the standing and layering time is 0.1 to 2 hours, and the phenol phase containing the organic solvent and the water phase containing the acidified aqueous solution of the organic amine are separated.

6. The method for separating a mixture of crude phenol and organic amine according to claim 2, wherein the acidified water is fed from the 1 st stage to a multistage countercurrent extraction apparatus, the organic solvent is fed from the 1 st stage to the multistage countercurrent extraction apparatus, the acidified crude phenol containing organic amine is fed from the 2 nd stage or together with the organic solvent to the multistage countercurrent extraction apparatus, and the extraction separation is completed by countercurrent contact.

7. The process according to any one of claims 1 to 6, wherein when the organic amine content in the organic solvent-containing phenol phase is greater than 0.1 wt%, the organic solvent-containing phenol phase is washed with water at least once until the organic amine content in the organic solvent-containing phenol phase is below 0.1 wt%;

the step of washing the phenol phase containing the organic solvent by water is to mix water with the phenol phase containing the organic solvent, introduce an acidifying agent for acidification treatment, then stand for layering, and separate to obtain the phenol phase containing the organic solvent and the water phase containing the organic amine acidified water solution; or, the step of washing the phenol phase containing the organic solvent by water is to respectively introduce acidulants into water and the phenol phase containing the organic solvent for acidification treatment, then mix the water and the phenol phase together, then stand the mixture for layering, and separate the mixture to obtain the phenol phase containing the organic solvent and the water phase containing the organic amine acidified water solution.

8. The method for separating a mixture of crude phenol and organic amine according to claim 7, wherein the mass ratio of the organic solvent-containing phenol phase to water is 1:0.1 to 1: 2.

9. The method for separating a mixture of crude phenol and organic amine according to any one of claims 1 to 6, wherein the crude phenol containing organic amine is a heavy phase obtained when phenol oil is extracted, and the content of organic amine is 10-80 wt%; wherein the organic amine is at least one of C2-C6 alcohol amine and dihydric alcohol amine.

10. The method for separating a mixture of crude phenol and organic amine according to any one of claims 1 to 6, wherein the organic solvent is at least one of C4-C8 alcohol, C6-C9 aromatic hydrocarbon, acetate, and ether.